1. Field of the Invention
The present invention relates generally to the field of coin checkers and acceptors, and more particularly, is directed to a coin or token sensing device capable of rapid acceptance of authentic coins or tokens and rapid rejection of counterfeits.
2. Description of the Prior Art
Automatic coin operated machines and mechanisms have become increasingly popular both in the United States and in many foreign countries. Early coin operated devices such as telephones have become increasingly more sophisticated in their coin accepting mechanisms and means have been provided to receive, check, sort, escrow and even return a large number of coins of varying denomination and size. Other coin or token activated machines, such as the popular coin operated washers and dryers, have resulted in the establishment of entirely new industries as a direct result of the improved nature of the coin accepting mechanisms. Of course, since the legalization of gambling in the states of Nevada and New Jersey and in various foreign countries, coin operated gaming devices known as slot machines now produce a most significant fraction of the entire gaming industry gross revenue. Other coin operated devices that have now established an accepted place in the daily routine of everyday life include cigarette vending machines, candy vending machines, article vending machines, liquid drink dispensing machines in either bottle or open cup configuration, and the like.
Just as sure as the various types of coin operated mechanisms have become increasingly popular, unscrupulous individuals have increasingly been tempted to develop slugs and other articles especially designed to defeat the coin checking facilities incorporated within the coin accepting mechanisms. Because of this, prior workers in the art have developed many construction features for use with the coin accepting mechanisms which have been particularly designed to minimize the acceptance of bad coins and slugs and to discourage tampering.
Coin gaming devices, such as slot machines, have now been designed to accept all denominations of coins from as low as five cents to as high as one dollar or more. Most recently, very valuable tokens, for example, tokens of $500 denomination have been introduced in the casinos and have become increasingly popular. With tokens of such value, it is extremely important that the coin checking systems function with extreme accuracy and with complete reliability. Coin checking mechanisms for this high end segment of the coin industry are currently of the type described in U.S. Pat. Nos. 4,326,621, 4,354,587, 4,334,604 and 4,359,148 to Davies and the coin checking device sold by Coin Mechanisms, Inc., Elmhurst, Ill. under the designation "Coin Comparitor Model CC-40."
While the above prior art coin acceptors or rejectors have become increasingly popular, these prior art designs suffer from a common design flaw in that the distance from the area wherein the coin or token is electronically tested and the gating mechanism that is employed to deflect a valid coin or token is too great. This distance is usually in the neighborhood of between 11/2 and 2 diameters of the coin or token being checked or more. This geometry determines that the coin or token being checked in the sensing area is not the same coin or token that is present within the accept or reject mechanism. The greater the distance between the coin checking and the coin gating provides an increased time gap wherein a skilled person can defeat the mechanism. With a sufficient time period within which to act, the coin checking mechanism can be defeated by quickly placing and feeding a counterfeit coin or token which is interleaved with a valid coin or token. When the time lag is of sufficient duration, there is a possibility that a skilled person can cheat the coin acceptor or rejector by feeding a spurious coin or token in rapid succession following a genuine coin. By pursuing this course, should the circuitry recognize the first coin as being genuine, the spurious coin quickly following in rapid succession may still be accepted by the machine because of the inability of the accept solenoid or other coin accept mechanism to respond quickly enough to reject the spurious coin.